1. Technical Field of the Invention
This invention relates to a thermosyphonic liquid phase method for reacting oxygen with isobutane to provide a solution comprising unreacted isobutane, tertiary butyl hydroperoxide, tertiary butyl alcohol and by-products and to a thermosyphonic reactor useful for the process.
2. Prior Art
Grane U.S. Pat. No. 3,907,902 is directed to a method for increasing the selectivity for tertiary butyl hydroperoxide during the liquid phase oxidation of isobutane with molecular oxygen by introducing a small amount of isopropyl alcohol or secondary butyl alcohol or isobutyl alcohol into the reaction zone.
Lutz et al. U.S. Pat. No. 4,404,406 is directed to a method for the preparation of tertiary butyl hydroperoxide by the direct oxidation of isobutane with oxygen wherein the oxidation is conducted in a dense super critical phase reaction mixture at a temperature in excess of the critical temperature of the mixture and at a pressure in excess of the critical pressure of the mixture.
Jubin U.S. Pat. No. 4,128,587 is directed to a method for regulating the conversion and selectivity obtained in oxidizing isobutane with molecular oxygen by regulating the concentration of tertiary butyl alcohol in an isobutane feed stream.
It is also known to promote the reaction of oxygen with isobutane or cumene by the use of a catalyst.
For example, Joris U.S. Pat. No. 2,577,768 is directed to the liquid phase oxidation of cumene with elemental oxygen in the presence of sodium bicarbonate. Johnston U.S. Pat. No. 3,825,605 is directed to the oxidation of isobutane to tertiary butyl alcohol and other by-products in the presence of a metal acetate catalyst. The use of sodium fluoride as a catalyst to promote the oxidation of cumene with molecular oxygen is disclosed in McAvoy U.S. Pat. No. 3,833,663. Barone in U.S. Pat. No. 4,152,358 discloses that metal phosphate catalysts can be used to promote the Oxidation of tertiary, arryl or cycloalkanes.
Grane et al. U.S. Pat. No. 4,294,999 discloses a method for the preparation of tertiary butyl alcohol by the oxidation of isobutane with molecular oxygen in the presence of a molybdenum catalyst. In U.S. Pat. No. 4,296,262, Grane et al. also disclose the use of molybdenum catalysts to promote the reaction of isobutane with molecular oxygen.
Worrell U.S. Pat. No. 4,296,263 is directed to a method for reacting a crude feed mixture of n-butane and isobutane with molecular oxygen in the presence of a catalyst.
It is also known to conduct gas-liquid chemical reactions in "closed loop" reactors as disclosed, for example, in Papp et al. U.S. Pat. No. 4,312,837 which discloses the use of a closed loop reactor comprising an ascending vertical tube and a descending vertical tube for the reaction of synthesis gas with an olefin in the presence of a catalyst. A reaction of this nature is also known as an Oxo synthesis.
Other references showing closed loop gas-liquid chemical reactors include Westerlund U.S. Pat. No. 3,502,443 which discloses a reactor useful for chlorine dioxide generation, Schuster et al. U.S. Pat. No. 4,482,692 which discloses a gas-liquid reaction conducted in a closed loop such as an oxygenation reaction. Other reactors are shown in Prave et al. U.S. Pat. Nos. 4,545,945 and 4,683,122 wherein a gas and a liquid are brought into contact in a dual zone reactor having an upflow portion and a downflow portion.
Vernon U.S. Pat. No. 3,212,860 discloses a process wherein two immiscible liquid chemicals are reacted in an upstanding reactor having a downflow portion and an upflow portion, such as an alkylation reaction wherein an olefin and isobutane are reacted.